Basic Jamma Harness Question

[susnet]

Hey Guys,

My arcade came with 6 buttons, I plugged in a Pandora's box and only 4 of the buttons worked for both players.

Initially I thought it was some dodgy soldering and lose wires but I now realise that 2 buttons for each player are not even wired to the harness. You can see from my picture they're wired separately, presumably they was plugged into another board this way at some point in their life.

So correct me if I'm wrong, but this is a 4 button Jamma harness?

Just confuses me slightly because it has empty pins, I don't have a diagram for it and even if I did the colour wires are all randomly hacked together in places.

I need to purchase a 6 button harness and rewire everything to it?

I've been avoiding replacing the Jamma harness because it looks scary but this might be the push I need to learn it and do it properly.

I see someone mention that modern Jamma harnesses are rubbish, is this one linked below ok or would you recommend something else?

https://www.arcadeworlduk.com/products/Black-JAMMA-Harness-6-Button-Wiring.html

Thanks

Paul

 

[The Last Bandit]

Jamma is a bit of a mess as far as standards go..

What you have there is a 'standard' Jamma loom with 4th button added to the Jamma edge and also a CPS2 kickharness for buttons 4,5,6.

You're also missing Video gnd and test button connections, which may cause problems later on if you start swapping in Jamma pcbs.

The loom you've linked to is fine for hooking up the Pandora's box (main reason modern ones are said to rubbish is the cheap ass wiring used for the power supplies which can't handle the current requirements on some power hungry Jamma boards).

But, these looms use a pin normally reserved for GND for Button 6 so you need to careful what Jamma boards you can plug in.

 

[FrancoB]

The JAMAM loom you have there looks to be wired quite nicely, it's also a Hirose CR7E-56DA-3.96E edge connector which is a really high quality edge connector. I would keep that all intact. You can easily add test etc wires to it if needs be.

I wouldn't recommend picking up the loom you linked to as the quality of them leaves a lot to be desired and the one you have already looks far superior.

As your buttons 4 5 and 6 are already wired to a CPS2 wired 'kick connector' you could use a JNS Atlas adapter:

This sits between your JAMMA loom and your Pandoras box. Your kick connector would plug directly into this. The adapter also sorts out the grounding differences between your JAMMA loom and the Pandoras box.

I think they might currently be out of production but you should be able to pick up a used one.

 

[susnet]

Thanks for coming back to me with this info, very helpful.

I'm going to order the JNX Atlas Adapter, looks like I can order it direct. However there are a few choices and I want to make sure I'm ordering the right one considering it's more expensive than I expected and it's coming from the states.

So from what you've told me it looks like I need:

JNX Atlas - CPS2

The other options are:

JNX Atlas DLX - Midway and CPS2

JNX Atlas DLX - CPS1 and CPS2

JNX Atlas - No Voltmeter - CPS1 & CPS2 (Cheaper - Do I need the voltmeter?)

Thanks again

 

[susnet]

Bump